Gallery Zone is a large shopping center downtown Daegu, which also houses a decent fitness club, sauna, and jjimjilbang. I stayed there one night last fall after partying downtown, and it served it's purpose. I had a hard time finding a lot of information about it, but I remember it being clean and reasonably quiet, though it wasn't very spacious. The sauna areas have windows to the outside so it's bright in the morning. Clearly, this spa's major draw is it's proximity to the party areas of downtown.
대구광역시 중구 삼덕동 1가 15-1번지 4층
Daegu, Jung Gu, Sam-deok Dong 1, building 15-1, 4th Floor
Open 24 hours a day/ 7 days a week
Gallery Zone website, then click on "휘트니스 존"
Wikimap of this location